inc/3rdparty/simplepie/SimplePie/Content/Type/Sniffer.php

   1 <?php
   2 /**
   3  * SimplePie
   4  *
   5  * A PHP-Based RSS and Atom Feed Framework.
   6  * Takes the hard work out of managing a complete RSS/Atom solution.
   7  *
   8  * Copyright (c) 2004-2009, Ryan Parman, Geoffrey Sneddon, Ryan McCue, and contributors
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without modification, are
  12  * permitted provided that the following conditions are met:
  13  *
  14  *      * Redistributions of source code must retain the above copyright notice, this list of
  15  *        conditions and the following disclaimer.
  16  *
  17  *      * Redistributions in binary form must reproduce the above copyright notice, this list
  18  *        of conditions and the following disclaimer in the documentation and/or other materials
  19  *        provided with the distribution.
  20  *
  21  *      * Neither the name of the SimplePie Team nor the names of its contributors may be used
  22  *        to endorse or promote products derived from this software without specific prior
  23  *        written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS
  26  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
  27  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS
  28  * AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  30  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  31  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  32  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  33  * POSSIBILITY OF SUCH DAMAGE.
  34  *
  35  * @package SimplePie
  36  * @version 1.3-dev
  37  * @copyright 2004-2010 Ryan Parman, Geoffrey Sneddon, Ryan McCue
  38  * @author Ryan Parman
  39  * @author Geoffrey Sneddon
  40  * @author Ryan McCue
  41  * @link http://simplepie.org/ SimplePie
  42  * @license http://www.opensource.org/licenses/bsd-license.php BSD License
  43  * @todo phpDoc comments
  44  */
  45
  46
  47 /**
  48  * Content-type sniffing
  49  *
  50  * Based on the rules in http://tools.ietf.org/html/draft-abarth-mime-sniff-06
  51  * @package SimplePie
  52  */
  53 class SimplePie_Content_Type_Sniffer
  54 {
  55         /**
  56          * File object
  57          *
  58          * @var SimplePie_File
  59          */
  60         var $file;
  61
  62         /**
  63          * Create an instance of the class with the input file
  64          *
  65          * @param SimplePie_Content_Type_Sniffer $file Input file
  66          */
  67         public function __construct($file)
  68         {
  69                 $this->file = $file;
  70         }
  71
  72         /**
  73          * Get the Content-Type of the specified file
  74          *
  75          * @return string Actual Content-Type
  76          */
  77         public function get_type()
  78         {
  79                 if (isset($this->file->headers['content-type']))
  80                 {
  81                         if (!isset($this->file->headers['content-encoding'])
  82                                 && ($this->file->headers['content-type'] === 'text/plain'
  83                                         || $this->file->headers['content-type'] === 'text/plain; charset=ISO-8859-1'
  84                                         || $this->file->headers['content-type'] === 'text/plain; charset=iso-8859-1'
  85                                         || $this->file->headers['content-type'] === 'text/plain; charset=UTF-8'))
  86                         {
  87                                 return $this->text_or_binary();
  88                         }
  89
  90                         if (($pos = strpos($this->file->headers['content-type'], ';')) !== false)
  91                         {
  92                                 $official = substr($this->file->headers['content-type'], 0, $pos);
  93                         }
  94                         else
  95                         {
  96                                 $official = $this->file->headers['content-type'];
  97                         }
  98                         $official = trim(strtolower($official));
  99
 100                         if ($official === 'unknown/unknown'
 101                                 || $official === 'application/unknown')
 102                         {
 103                                 return $this->unknown();
 104                         }
 105                         elseif (substr($official, -4) === '+xml'
 106                                 || $official === 'text/xml'
 107                                 || $official === 'application/xml')
 108                         {
 109                                 return $official;
 110                         }
 111                         elseif (substr($official, 0, 6) === 'image/')
 112                         {
 113                                 if ($return = $this->image())
 114                                 {
 115                                         return $return;
 116                                 }
 117                                 else
 118                                 {
 119                                         return $official;
 120                                 }
 121                         }
 122                         elseif ($official === 'text/html')
 123                         {
 124                                 return $this->feed_or_html();
 125                         }
 126                         else
 127                         {
 128                                 return $official;
 129                         }
 130                 }
 131                 else
 132                 {
 133                         return $this->unknown();
 134                 }
 135         }
 136
 137         /**
 138          * Sniff text or binary
 139          *
 140          * @return string Actual Content-Type
 141          */
 142         public function text_or_binary()
 143         {
 144                 if (substr($this->file->body, 0, 2) === "\xFE\xFF"
 145                         || substr($this->file->body, 0, 2) === "\xFF\xFE"
 146                         || substr($this->file->body, 0, 4) === "\x00\x00\xFE\xFF"
 147                         || substr($this->file->body, 0, 3) === "\xEF\xBB\xBF")
 148                 {
 149                         return 'text/plain';
 150                 }
 151                 elseif (preg_match('/[\x00-\x08\x0E-\x1A\x1C-\x1F]/', $this->file->body))
 152                 {
 153                         return 'application/octect-stream';
 154                 }
 155                 else
 156                 {
 157                         return 'text/plain';
 158                 }
 159         }
 160
 161         /**
 162          * Sniff unknown
 163          *
 164          * @return string Actual Content-Type
 165          */
 166         public function unknown()
 167         {
 168                 $ws = strspn($this->file->body, "\x09\x0A\x0B\x0C\x0D\x20");
 169                 if (strtolower(substr($this->file->body, $ws, 14)) === '<!doctype html'
 170                         || strtolower(substr($this->file->body, $ws, 5)) === '<html'
 171                         || strtolower(substr($this->file->body, $ws, 7)) === '<script')
 172                 {
 173                         return 'text/html';
 174                 }
 175                 elseif (substr($this->file->body, 0, 5) === '%PDF-')
 176                 {
 177                         return 'application/pdf';
 178                 }
 179                 elseif (substr($this->file->body, 0, 11) === '%!PS-Adobe-')
 180                 {
 181                         return 'application/postscript';
 182                 }
 183                 elseif (substr($this->file->body, 0, 6) === 'GIF87a'
 184                         || substr($this->file->body, 0, 6) === 'GIF89a')
 185                 {
 186                         return 'image/gif';
 187                 }
 188                 elseif (substr($this->file->body, 0, 8) === "\x89\x50\x4E\x47\x0D\x0A\x1A\x0A")
 189                 {
 190                         return 'image/png';
 191                 }
 192                 elseif (substr($this->file->body, 0, 3) === "\xFF\xD8\xFF")
 193                 {
 194                         return 'image/jpeg';
 195                 }
 196                 elseif (substr($this->file->body, 0, 2) === "\x42\x4D")
 197                 {
 198                         return 'image/bmp';
 199                 }
 200                 elseif (substr($this->file->body, 0, 4) === "\x00\x00\x01\x00")
 201                 {
 202                         return 'image/vnd.microsoft.icon';
 203                 }
 204                 else
 205                 {
 206                         return $this->text_or_binary();
 207                 }
 208         }
 209
 210         /**
 211          * Sniff images
 212          *
 213          * @return string Actual Content-Type
 214          */
 215         public function image()
 216         {
 217                 if (substr($this->file->body, 0, 6) === 'GIF87a'
 218                         || substr($this->file->body, 0, 6) === 'GIF89a')
 219                 {
 220                         return 'image/gif';
 221                 }
 222                 elseif (substr($this->file->body, 0, 8) === "\x89\x50\x4E\x47\x0D\x0A\x1A\x0A")
 223                 {
 224                         return 'image/png';
 225                 }
 226                 elseif (substr($this->file->body, 0, 3) === "\xFF\xD8\xFF")
 227                 {
 228                         return 'image/jpeg';
 229                 }
 230                 elseif (substr($this->file->body, 0, 2) === "\x42\x4D")
 231                 {
 232                         return 'image/bmp';
 233                 }
 234                 elseif (substr($this->file->body, 0, 4) === "\x00\x00\x01\x00")
 235                 {
 236                         return 'image/vnd.microsoft.icon';
 237                 }
 238                 else
 239                 {
 240                         return false;
 241                 }
 242         }
 243
 244         /**
 245          * Sniff HTML
 246          *
 247          * @return string Actual Content-Type
 248          */
 249         public function feed_or_html()
 250         {
 251                 $len = strlen($this->file->body);
 252                 $pos = strspn($this->file->body, "\x09\x0A\x0D\x20");
 253
 254                 while ($pos < $len)
 255                 {
 256                         switch ($this->file->body[$pos])
 257                         {
 258                                 case "\x09":
 259                                 case "\x0A":
 260                                 case "\x0D":
 261                                 case "\x20":
 262                                         $pos += strspn($this->file->body, "\x09\x0A\x0D\x20", $pos);
 263                                         continue 2;
 264
 265                                 case '<':
 266                                         $pos++;
 267                                         break;
 268
 269                                 default:
 270                                         return 'text/html';
 271                         }
 272
 273                         if (substr($this->file->body, $pos, 3) === '!--')
 274                         {
 275                                 $pos += 3;
 276                                 if ($pos < $len && ($pos = strpos($this->file->body, '-->', $pos)) !== false)
 277                                 {
 278                                         $pos += 3;
 279                                 }
 280                                 else
 281                                 {
 282                                         return 'text/html';
 283                                 }
 284                         }
 285                         elseif (substr($this->file->body, $pos, 1) === '!')
 286                         {
 287                                 if ($pos < $len && ($pos = strpos($this->file->body, '>', $pos)) !== false)
 288                                 {
 289                                         $pos++;
 290                                 }
 291                                 else
 292                                 {
 293                                         return 'text/html';
 294                                 }
 295                         }
 296                         elseif (substr($this->file->body, $pos, 1) === '?')
 297                         {
 298                                 if ($pos < $len && ($pos = strpos($this->file->body, '?>', $pos)) !== false)
 299                                 {
 300                                         $pos += 2;
 301                                 }
 302                                 else
 303                                 {
 304                                         return 'text/html';
 305                                 }
 306                         }
 307                         elseif (substr($this->file->body, $pos, 3) === 'rss'
 308                                 || substr($this->file->body, $pos, 7) === 'rdf:RDF')
 309                         {
 310                                 return 'application/rss+xml';
 311                         }
 312                         elseif (substr($this->file->body, $pos, 4) === 'feed')
 313                         {
 314                                 return 'application/atom+xml';
 315                         }
 316                         else
 317                         {
 318                                 return 'text/html';
 319                         }
 320                 }
 321
 322                 return 'text/html';
 323         }
 324 }
 325